Support InputMethodManager#updateCursorAnchorInfo for Android 5.0

content/public/android/java/src/org/chromium/content/browser/input/CursorAnchorInfoController.java

Index: content/public/android/java/src/org/chromium/content/browser/input/CursorAnchorInfoController.java
diff --git a/content/public/android/java/src/org/chromium/content/browser/input/CursorAnchorInfoController.java b/content/public/android/java/src/org/chromium/content/browser/input/CursorAnchorInfoController.java
new file mode 100644
index 0000000000000000000000000000000000000000..17c1bd5db04dd08c6ce7092736ab55e405c0f376
--- /dev/null
+++ b/content/public/android/java/src/org/chromium/content/browser/input/CursorAnchorInfoController.java
@@ -0,0 +1,467 @@
+// Copyright 2014 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+package org.chromium.content.browser.input;
+
+import android.graphics.Matrix;
+import android.graphics.RectF;
+import android.os.Build;
+import android.text.TextUtils;
+import android.view.View;
+import android.view.inputmethod.CursorAnchorInfo;
+import android.view.inputmethod.InputConnection;
+
+import org.chromium.base.CommandLine;
+import org.chromium.base.VisibleForTesting;
+import org.chromium.content.browser.RenderCoordinates;
+import org.chromium.content.common.ContentSwitches;
+
+import java.util.Arrays;
+
+import javax.annotation.Nonnull;
+import javax.annotation.Nullable;
+
+/*
+ * A state machine interface which receives Chromium internal events to determines when to call
+ * {@link InputMethodManager#updateCursorAnchorInfo(View, CursorAnchorInfo)}. This interface is
+ * also used in unit tests to mock out {@link CursorAnchorInfo}, which is available only in
+ * Android 5.0 (Lollipop) and later.
+ */
+final class CursorAnchorInfoController {
+    /**
+     * An interface to mock out {@link View#getLocationOnScreen(int[])} for testing.
+     */
+    public interface ViewDelegate {
+        void getLocationOnScreen(View view, int[] location);
+    }
+
+    private static final class CursorAnchorInfoWrapperImpl implements CursorAnchorInfoWrapper {
+        private static final class Builder implements CursorAnchorInfoWrapper.Builder {
+            private final CursorAnchorInfo.Builder mBuilder = new CursorAnchorInfo.Builder();
+
+            @Override
+            public CursorAnchorInfoWrapper.Builder setSelectionRange(int newStart, int newEnd) {
+                mBuilder.setSelectionRange(newStart, newEnd);
+                return this;
+            }
+
+            @Override
+            public CursorAnchorInfoWrapper.Builder setComposingText(
+                    int composingTextStart, CharSequence composingText) {
+                mBuilder.setComposingText(composingTextStart, composingText);
+                return this;
+            }
+
+            @Override
+            public CursorAnchorInfoWrapper.Builder setInsertionMarkerLocation(
+                    float horizontalPosition, float lineTop, float lineBaseline, float lineBottom,
+                    int flags) {
+                mBuilder.setInsertionMarkerLocation(horizontalPosition, lineTop, lineBaseline,
+                        lineBottom, flags);
+                return this;
+            }
+
+            @Override
+            public CursorAnchorInfoWrapper.Builder addCharacterBounds(
+                    int index, float left, float top, float right, float bottom, int flags) {
+                mBuilder.addCharacterBounds(index, left, top, right, bottom, flags);
+                return this;
+            }
+
+            @Override
+            public CursorAnchorInfoWrapper.Builder setMatrix(Matrix matrix) {
+                mBuilder.setMatrix(matrix);
+                return this;
+            }
+
+            @Override
+            public CursorAnchorInfoWrapper build() {
+                return new CursorAnchorInfoWrapperImpl(mBuilder.build());
+            }
+
+            @Override
+            public void reset() {
+                mBuilder.reset();
+            }
+        }
+
+        private final CursorAnchorInfo mObj;
+        public CursorAnchorInfoWrapperImpl(CursorAnchorInfo obj) {
+            mObj = obj;
+        }
+
+        @Override
+        public int getSelectionStart() {
+            return mObj.getSelectionStart();
+        }
+
+        @Override
+        public int getSelectionEnd() {
+            return mObj.getSelectionEnd();
+        }
+
+        @Override
+        public int getComposingTextStart() {
+            return mObj.getComposingTextStart();
+        }
+
+        @Override
+        public CharSequence getComposingText() {
+            return mObj.getComposingText();
+        }
+
+        @Override
+        public int getInsertionMarkerFlags() {
+            return mObj.getInsertionMarkerFlags();
+        }
+
+        @Override
+        public float getInsertionMarkerHorizontal() {
+            return mObj.getInsertionMarkerHorizontal();
+        }
+
+        @Override
+        public float getInsertionMarkerTop() {
+            return mObj.getInsertionMarkerTop();
+        }
+
+        @Override
+        public float getInsertionMarkerBaseline() {
+            return mObj.getInsertionMarkerBaseline();
+        }
+
+        @Override
+        public float getInsertionMarkerBottom() {
+            return mObj.getInsertionMarkerBottom();
+        }
+
+        @Override
+        public RectF getCharacterBounds(int index) {
+            return mObj.getCharacterBounds(index);
+        }
+
+        @Override
+        public int getCharacterBoundsFlags(int index) {
+            return mObj.getCharacterBoundsFlags(index);
+        }
+
+        @Override
+        public Matrix getMatrix() {
+            return mObj.getMatrix();
+        }
+
+        @Override
+        public Object unwrap() {
+            return mObj;
+        }
+    }
+
+    @Nullable
+    private CharSequence mText;
+    private int mSelectionStart;
+    private int mSelectionEnd;
+    private int mComposingTextStart;
+    private int mComposingTextEnd;
+    @Nullable
+    private float[] mCompositionCharacterBounds;
+    private boolean mHasInsertionMarker;
+    private boolean mIsInsertionMarkerVisible;
+    private float mInsertionMarkerHorizontal;
+    private float mInsertionMarkerTop;
+    private float mInsertionMarkerBottom;
+    private float mScale;
+    private float mTranslationX;
+    private float mTranslationY;
+    private boolean mIsEditable;
+    private boolean mHasPendingRequest;
+    private boolean mMonitorModeEnabled;
+    private boolean mHasCoordinateInfo;
+
+    @Nonnull
+    private final CursorAnchorInfoWrapper.Builder mCursorAnchorInfoBuilder;
+    @Nullable
+    private volatile CursorAnchorInfoWrapper mLastCursorAnchorInfo;
+
+    @Nonnull
+    private final Matrix mMatrix = new Matrix();
+    @Nonnull
+    private final int[] mViewOrigin = new int[2];
+    @Nonnull
+    private final ViewDelegate mViewDelegate;
+
+    @Nullable
+    private InputMethodManagerWrapper mInputMethodManagerWrapper;
+
+    private static final boolean sIsSupported = isSupportedInit();
+
+    /**
+     * @return {@code true} if {@link CursorAnchorInfo} is supported on this device.
+     */
+    private static boolean isSupportedInit() {
+        if (Build.VERSION.SDK_INT < Build.VERSION_CODES.LOLLIPOP)
+            return false;
+        if (CommandLine.getInstance() != null
+                && !CommandLine.getInstance().hasSwitch(ContentSwitches.ENABLE_CURSOR_ANCHOR_INFO))
+            return false;
+        return true;
+    }
+
+    /**
+     * @return {@code true} if {@link CursorAnchorInfo} is supported on this device.
+     */
+    public static boolean isSupported() {
+        return sIsSupported;
+    }
+
+    private CursorAnchorInfoController(InputMethodManagerWrapper inputMethodManagerWrapper,
+            CursorAnchorInfoWrapper.Builder builder,
+            ViewDelegate viewDelegate) {
+        mInputMethodManagerWrapper = inputMethodManagerWrapper;
+        mCursorAnchorInfoBuilder = builder;
+        mViewDelegate = viewDelegate;
+    }
+
+    public static CursorAnchorInfoController create(
+            InputMethodManagerWrapper inputMethodManagerWrapper) {
+        return isSupported() ? new CursorAnchorInfoController(inputMethodManagerWrapper,
+                new CursorAnchorInfoWrapperImpl.Builder(), new ViewDelegate() {
+                    @Override
+                    public void getLocationOnScreen(View view, int[] location) {
+                        view.getLocationOnScreen(location);
+                    }
+                }) : null;
+    }
+
+    @VisibleForTesting
+    public void setInputMethodManagerWrapper(InputMethodManagerWrapper inputMethodManagerWrapper) {
+        mInputMethodManagerWrapper = inputMethodManagerWrapper;
+    }
+
+    @VisibleForTesting
+    public static CursorAnchorInfoController createForTest(
+            InputMethodManagerWrapper inputMethodManagerWrapper,
+            CursorAnchorInfoWrapper.Builder builder,
+            ViewDelegate viewDelegate) {
+        return new CursorAnchorInfoController(inputMethodManagerWrapper, builder, viewDelegate);
+    }
+
+    /**
+     * @return Current composing text (if any). {@code null} otherwise.
+     */
+    @Nullable
+    public CharSequence getComposingText() {
+        if (mText == null)
+            return null;
+        if (0 <= mComposingTextStart && mComposingTextStart <= mText.length())
+            return mText.subSequence(mComposingTextStart, mComposingTextEnd);
+        return "";
+    }
+
+    /**
+     * Updates text in the focused text area, selection range, and the composing text range.
+     * @param text Text in the focused text field.
+     * @param composingTextStart Index where the text composition starts. {@code -1} if there is
+     * no selection.
+     * @param composingTextEnd Index where the text composition ends. {@code -1} if there is no
+     * selection.
+     * @param selectionStart Index where the text selection starts. {@code -1} if there is no
+     * selection.
+     * @param selectionEnd Index where the text selection ends. {@code -1} if there is no
+     * selection.
+     */
+    public void updateTextAndSelection(CharSequence text, int composingTextStart,
+            int composingTextEnd, int selectionStart, int selectionEnd) {
+        if (!mIsEditable)
+            return;
+        if (mLastCursorAnchorInfo == null && mMonitorModeEnabled)
+            mHasPendingRequest = true;
+        if (mLastCursorAnchorInfo != null && !mHasPendingRequest) {
+            if (!TextUtils.equals(text, mText) || selectionStart != mSelectionStart
+                    || selectionEnd != mSelectionEnd || composingTextStart != mComposingTextStart
+                    || composingTextEnd != mComposingTextEnd) {
+                mLastCursorAnchorInfo = null;
+                if (mMonitorModeEnabled) {
+                    mHasPendingRequest = true;
+                }
+            }
+        }
+        mText = text;
+        mSelectionStart = selectionStart;
+        mSelectionEnd = selectionEnd;
+        mComposingTextStart = composingTextStart;
+        mComposingTextEnd = composingTextEnd;
+    }
+
+    /**
+     * Sets positional information of composing text as an array of character bounds.
+     * @param compositionCharacterBounds Array of character bounds in local coordinates.
+     */
+    public void setCompositionCharacterBounds(float[] compositionCharacterBounds) {
+        if (!mIsEditable)
+            return;
+        if (mLastCursorAnchorInfo == null && mMonitorModeEnabled)
+            mHasPendingRequest = true;
+        if (mLastCursorAnchorInfo != null && !mHasPendingRequest) {
+            if (!Arrays.equals(compositionCharacterBounds, mCompositionCharacterBounds)) {
+                mLastCursorAnchorInfo = null;
+                if (mMonitorModeEnabled) {
+                    mHasPendingRequest = true;
+                }
+            }
+        }
+        mCompositionCharacterBounds = compositionCharacterBounds;
+    }
+
+    /**
+     * Sets coordinates system parameters and selection marker information.
+     * @param hasInsertionMarker {@code true} if the insertion marker exists.
+     * @param isInsertionMarkerVisible {@code true} if the insertion insertion marker is visible.
+     * @param insertionMarkerHorizontal X coordinate of the top of the first selection marker.
+     * @param insertionMarkerTop Y coordinate of the top of the first selection marker.
+     * @param insertionMarkerBottom Y coordinate of the bottom of the first selection marker.
+     * @param view The attached view.
+     */
+    public void onUpdateFrameInfo(@Nonnull RenderCoordinates renderCoordinates,
+            boolean hasInsertionMarker, boolean isInsertionMarkerVisible,
+            float insertionMarkerHorizontal, float insertionMarkerTop,
+            float insertionMarkerBottom, @Nonnull View view) {
+        if (!mIsEditable)
+            return;
+
+        float scale =
+                renderCoordinates.getPageScaleFactor() * renderCoordinates.getDeviceScaleFactor();
+        float translationX;
+        float translationY;
+        // Reuse {@param #mViewOrigin} to avoid object creation, as this method is supposed to be
+        // called at relatively high rate.
+        mViewDelegate.getLocationOnScreen(view, mViewOrigin);
+        translationX = -renderCoordinates.getScrollX() * scale + mViewOrigin[0];
+        translationY = -renderCoordinates.getScrollY() * scale
+                + renderCoordinates.getContentOffsetYPix() + mViewOrigin[1];
+
+        if (mLastCursorAnchorInfo == null && mMonitorModeEnabled)
+            mHasPendingRequest = true;
+        if (mLastCursorAnchorInfo != null && !mHasPendingRequest) {
+            if (!mHasCoordinateInfo
+                    || scale != mScale
+                    || translationX != mTranslationX
+                    || translationY != mTranslationY
+                    || hasInsertionMarker != mHasInsertionMarker
+                    || isInsertionMarkerVisible != mIsInsertionMarkerVisible
+                    || insertionMarkerHorizontal != mInsertionMarkerHorizontal
+                    || insertionMarkerTop != mInsertionMarkerTop
+                    || insertionMarkerBottom != mInsertionMarkerBottom) {
+                mLastCursorAnchorInfo = null;
+                if (mMonitorModeEnabled) {
+                    mHasPendingRequest = true;
+                }
+            }
+        }
+
+        mHasInsertionMarker = hasInsertionMarker;
+        mIsInsertionMarkerVisible = isInsertionMarkerVisible;
+        mInsertionMarkerHorizontal = insertionMarkerHorizontal;
+        mInsertionMarkerTop = insertionMarkerTop;
+        mInsertionMarkerBottom = insertionMarkerBottom;
+        mScale = scale;
+        mTranslationX = translationX;
+        mTranslationY = translationY;
+        mHasCoordinateInfo = true;
+        if (mLastCursorAnchorInfo == null && mHasPendingRequest)
+            updateCursorAnchorInfo();
+        if (mLastCursorAnchorInfo != null && mHasPendingRequest) {
+            if (mInputMethodManagerWrapper != null) {
+                mInputMethodManagerWrapper.updateCursorAnchorInfo(view, mLastCursorAnchorInfo);
+            }
+            mHasPendingRequest = false;
+        }
+    }
+
+    public void focusedNodeChanged(boolean isEditable) {
+        mIsEditable = isEditable;
+        mHasCoordinateInfo = false;
+        mText = null;
+        mSelectionStart = -1;
+        mSelectionEnd = -1;
+        mComposingTextStart = -1;
+        mComposingTextEnd = -1;
+        mCompositionCharacterBounds = null;
+        mHasInsertionMarker = false;
+        mInsertionMarkerHorizontal = Float.NaN;
+        mInsertionMarkerTop = Float.NaN;
+        mInsertionMarkerBottom = Float.NaN;
+        mScale = 1.0f;
+        mTranslationX = 0.0f;
+        mTranslationY = 0.0f;
+        mLastCursorAnchorInfo = null;
+        mCursorAnchorInfoBuilder.reset();
+    }
+
+    public boolean onRequestCursorUpdates(int cursorUpdateMode, @Nonnull View view) {
+        if (!mIsEditable)
+            return false;
+        final int knownRequestCursorUpdatesFlags =
+                InputConnection.CURSOR_UPDATE_MONITOR | InputConnection.CURSOR_UPDATE_IMMEDIATE;
+        if ((cursorUpdateMode & ~knownRequestCursorUpdatesFlags) != 0) {
+            // Does nothing when at least one unknown bit flag is set.
+            return false;
+        }
+        boolean updateImmediate =
+                (cursorUpdateMode & InputConnection.CURSOR_UPDATE_IMMEDIATE) != 0;
+        boolean updateMonitor =
+                (cursorUpdateMode & InputConnection.CURSOR_UPDATE_MONITOR) != 0;
+        mMonitorModeEnabled = updateMonitor;
+        if (updateImmediate) {
+            if (mLastCursorAnchorInfo == null && mHasCoordinateInfo) {
+                updateCursorAnchorInfo();
+            }
+            if (mLastCursorAnchorInfo != null) {
+                if (mInputMethodManagerWrapper != null) {
+                    mInputMethodManagerWrapper.updateCursorAnchorInfo(view, mLastCursorAnchorInfo);
+                }
+            } else {
+                mHasPendingRequest = true;
+            }
+        }
+        return true;
+    }
+
+    private void updateCursorAnchorInfo() {
+        synchronized (mCursorAnchorInfoBuilder) {
+            CharSequence composingText = getComposingText();
+            int composingTextStart = mComposingTextStart;
+            if (composingText != null) {
+                mCursorAnchorInfoBuilder.setComposingText(composingTextStart, composingText);
+                float[] compositionCharacterBounds = mCompositionCharacterBounds;
+                if (compositionCharacterBounds != null) {
+                    int numCharacter = compositionCharacterBounds.length / 4;
+                    for (int i = 0; i < numCharacter; ++i) {
+                        float left = compositionCharacterBounds[i * 4];
+                        float top = compositionCharacterBounds[i * 4 + 1];
+                        float right = compositionCharacterBounds[i * 4 + 2];
+                        float bottom = compositionCharacterBounds[i * 4 + 3];
+                        int charIndex = composingTextStart + i;
+                        mCursorAnchorInfoBuilder.addCharacterBounds(charIndex, left, top, right,
+                                bottom, CursorAnchorInfo.FLAG_HAS_VISIBLE_REGION);
+                    }
+                }
+            }
+            mCursorAnchorInfoBuilder.setSelectionRange(mSelectionStart, mSelectionEnd);
+            mMatrix.setScale(mScale, mScale);
+            mMatrix.postTranslate(mTranslationX, mTranslationY);
+            mCursorAnchorInfoBuilder.setMatrix(mMatrix);
+            if (mHasInsertionMarker) {
+                mCursorAnchorInfoBuilder.setInsertionMarkerLocation(
+                        mInsertionMarkerHorizontal,
+                        mInsertionMarkerTop,
+                        mInsertionMarkerBottom,
+                        mInsertionMarkerBottom,
+                        mIsInsertionMarkerVisible ? CursorAnchorInfo.FLAG_HAS_VISIBLE_REGION :
+                            CursorAnchorInfo.FLAG_HAS_INVISIBLE_REGION);
+            }
+            mLastCursorAnchorInfo = mCursorAnchorInfoBuilder.build();
+            mCursorAnchorInfoBuilder.reset();
+        }
+    }
+}